Answers

Add 20/90 and 40/21

1^st number: 20/90, 2^nd number: 1 19/21

20/90 + 40/21 is 134/63.

Steps for adding fractions

1. Find the least common denominator or LCM of the two denominators:
   LCM of 90 and 21 is 630
   
   Next, find the equivalent fraction of both fractional numbers with denominator 630
2. For the 1st fraction, since 90 × 7 = 630,
   20/90 = 20 × 7/90 × 7 = 140/630
3. Likewise, for the 2nd fraction, since 21 × 30 = 630,
   40/21 = 40 × 30/21 × 30 = 1200/630
4. Add the two like fractions:
   140/630 + 1200/630 = 140 + 1200/630 = 1340/630
5. 1340/630 simplified gives 134/63
6. So, 20/90 + 40/21 = 134/63
   In mixed form: 28/63

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